<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script>
       // alert.call(window,"show call");

       function SuperType() {
           this.colors = ['red', 'blue'];
       }

       function SubType() {
           // 继承了SuperType
           SuperType.call(this);
       }

       var ins1 = new SubType();
       ins1.colors.push('yellow');
       console.log(ins1.colors); // “red, blue, yellow”

       var ins2 = new SubType();
       console.log(ins2.colors); // “red, blue”

    </script>
</head>
<body>
借用构造函数
</body>
</html>